A belt and a wallet cost $42 while 7 belts and 4 wallets cost $213. Find the cost of a belt and a wallet.
"A belt and a wallet cost $42"
I THINK you might want the cost of a wallet and the cost of a belt.
b + w = 42 b = 42-w sub this into the following eq
7b + 4w = 213
7(42-w) + 4w = 213 solve for 'w' then sub this value into one of the equations to solve for 'b'
This can be written as a system of equations to solve.
Let b be the number of belts and w be the number of wallets.
Multiply the first equation by 4
Subtract this equation from the second.
The ws cancel out!
This can be substituted back into the first equation
Double check to make sure these numbers work:
15+27=42, this one works
7(15)+4(27)=213 This one also works so this is the correct answer.